<?phpclass test{  public $x=1;  public $setting;  //負責生成其他對象的類或方法,這就是工廠模式  public function getSetting(){    if(!$this->setting){      $this->setting=new Setting();    }    return $this->setting;  }}class Setting{  public function __construct(){    echo 1111;  }}$test=new test();$setting=$test->getSetting();$setting2=$test->getSetting();  //判斷兩個對象是否是同一個對象var_dump($setting===$setting2);//看編號,也能看出來var_dump($setting);var_dump($setting2);    //屬性中有減號的處理$name="x-b";$test->$name=2; var_dump($test);  //$test->x-b;//直接使用上面的屬性,會被認為是一個減號/*報錯:PHP Notice: Use of undefined constant b - assumed 'b' in D:/phpServer/WWW/test/test.php on line 11 Notice: Use of undefined constant b - assumed 'b' in D:/phpServer/WWW/test/test.php on line 11 */ echo $test->{'x-b'}; //這種屬性里面有-的這樣包一下